Sea level rise hot spots—bursts of accelerated sea rise that last three to five years—happen along the U.S. East Coast thanks to a one-two punch from naturally occurring climate variations, a new University of Florida study shows.

After UF scientists identified a hot spot reaching from Cape Hatteras to Miami, they probed the causes by analyzing tidal and climate data for the U.S. eastern seaboard. The new study, published online today in Geophysical Research Letters, shows that seas rose in the southeastern U.S. between 2011 and 2015 by more than six times the global average sea level rise that is already happening due to human-induced global warming.

The study's findings suggest that future sea level rise resulting from global warming will also have these hot spot periods superimposed on top of steadily rising seas, said study co-author Andrea Dutton, assistant professor in UF's department of geological sciences in the College of Liberal Arts and Sciences.

"The important point here is that smooth projections of sea level rise do not capture this variability, so adverse effects of sea level rise may occur before they are predicted to happen," Dutton said. "The entire U.S. Atlantic coastline is vulnerable to these hot spots that may amplify the severity of coastal flooding."

The combined effects of El Niño (ENSO) and the North Atlantic Oscillation (NAO), both of which are naturally occurring climate processes, drove the recent hot spot, according to the study. Study authors also discovered similar hot spots at various positions along the U.S. eastern seaboard over the past century. They found that these past hot spots are also explained by the combined influence of ENSO and NAO.

The finding challenges previous arguments that a hot spot north of Cape Hatteras over the past few decades was due to a slowdown of circulation in the North Atlantic, which is itself due to global warming. Instead, study authors discovered the combination of these two naturally occurring ocean-atmosphere processes explained both the timing and the location of hot spots observed along the entire U.S. Atlantic coast, Dutton said.

While a slowdown of circulation in the North Atlantic can further exacerbate sea level rise in the northeast, it does not explain the accelerations observed in the southeast, and was not required to explain the hot spots observed in the northeast, according to the study.

The authors found that hot spots observed over the past century were created by the influence of ENSO that affects the amount of water that accumulates in the western portion of the North Atlantic and causes seas to rise along the entire U.S. Atlantic coast. This sea level rise is then concentrated to the north or south by the NAO, which is a measure of the atmospheric pressure difference between Iceland and the Azores.

The telling hot spot recently observed in the southeast was discovered when the Indian River Lagoon on Florida's Atlantic coast, known for its algae blooms and blankets of dead fish, became much saltier after 2011, and study lead author Arnoldo Valle-Levinson, professor of civil and coastal engineering sciences in UF's College of Engineering, began to investigate the situation. He checked local tidal gauges, revealing that seas in the region were rising nearly 10 times faster than the long-term rate recorded in that region. When he reviewed tidal data for the entire eastern seaboard, he found similar numbers for all the tide gauge stations south of Cape Hatteras, revealing the regional extent of the hot spot.

Valle-Levinson said hot spots are difficult to predict and it's not clear if the hot spots will worsen with time. By decreasing emissions, he said we may be able to stabilize rising seas long-term, but the trend will likely be difficult to reverse.

"It's amazing to see construction along the East Coast. That's the worst place to build anything," said Valle-Levinson, who described the future for some southeastern U.S. cities as "Venice-like." "We need to understand that the ocean is coming."

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Assuming you're referring to the article's link to Phys.org's "sea level rise" tag, which includes an excerpt from WIkipedia's "Sea level rise" article. That article does not say that thermal expansion is "the" principal mechanism, it says the rise is "usually attributed" to both TE and melting ice sheets / glaciers. But since you mentioned only TE in your broken English despite the article mentioning both it's safe to assume you're lying, inserting "[the] principal mechanism".

Also you agree that 1993-2003 is "an undisputed time of temperature rise", which is honest. But then you're disappointed that the article accepts global warming as a premise, even as you agree the globe warmed. Which is lying - really stupid lying.

You ignore that the article does point out that hot spots are "superimposed" on other rise.

@Turgent, you imply/assert that anything that refers to or accepts the impacts of global warming is necessarily bad science. Global warming is supported by evidence. Opposition to the idea of global warming is not; instead, it is based entirely in petroleum-funded, fear-based, knee-jerk rejection of science. So who are you to talk about what "good science" is?

Reference Link to "sea level rise":1. Explains that thermal expansion is principal mechanism of sea level rise.2. Identifies 1993-2003 as range of data which does correlate to an undisputed time of temperature rise.3. Provides confidence intervals.4. Does project to 2100 however provides the range of uncertainty 90 to 880 mm, with a central value of 480 mm5. Soft side is source Wikipedia

Identifies hot spots as ENSN and NAO phenomenon rather than global warming. Doesn't deny, just doesn't associate with GW.

I appreciate your balanced approach to the GW issues/observations. However, please be careful not to fall into the bias trap of 'missing' the overarching problem: Climate processes/patterns in the transitional/longterm: extreme 'swings' of previously tolerable 'patterns' in atmos/ocean cycles/variables. You agree the TREND is BAD?

Turgent has invested in a delusion, which requires vigorous defense these days. His motivation exists outside the realm of logic or reason, although he is drawn towards attempts to disguise it as such. That is also part of his delusion maintenance strategy. Notice he mentions the word "Science" straight away, while the reality is that science has zero impact on his motivations.

My post was basically a book report where one reports their conclusions and opinion. A critical analysis is verboten? Who am I to make a judgement about "good science". It is good science relative to some junk science. Of course this is an opinion. Is there something wrong with an opinion which does not undercut any substance of the article?

Name calling and accusation of lying.

A lot of you are really sick. Your emotional filters reveal loss of all common sense.

Real sick Os.

So sad. Anything I post from hereon will automatically be seen as bad through you jaundice eyes. Read Ayn Rand's Atlas Shrugged with special attention to the State Science Institute.

If the trend is long term, rapid, and substantial it hard not to imagine it as being other than destructive and very much so. Seeing the postulated negative effects of GW are so many I wonder if we may see the return of the Malthusian Trap on a global scale, despite technology. I really wonder if there are any climatic self-regulatory systems (Gaia hypothesis) which will kick in to moderate temperature should GW go beyond some threshold. It would be nice to hear some optimist science on that subject, of which there is some.

I really wonder if there are any climatic self-regulatory systems (Gaia hypothesis)

so, the science is about facts, and as noted we see the current known regulatory systems (like oceans) being highly affected by AGWagain, this is directly tied to the AGW and the current rate of warming that is unprecedented in history

i can provide examples of your denier rhetoric if you likehowever, i want you to consider the sources you've presented for your claims... and then read and understand the following: http://www.drexel...nge.ashx

also note: it doesn't matter what you think or believe as any critical thinker will read those links and see your delusional actions and beliefs for themselves

Show some personal understanding ...expressing it yourself

so... even though i can present relevant validated science which represents refutation for your beliefs, i don't understand what you're saying because i don't put it in my own words that you're refusing to read anyway?

If the trend is long term, rapid, and substantial it hard not to imagine it as being other than destructive and very much so. Seeing the postulated negative effects of GW are so many I wonder if we may see the return of the Malthusian Trap on a global scale, despite technology. I really wonder if there are any climatic self-regulatory systems (Gaia hypothesis) which will kick in to moderate temperature should GW go beyond some threshold. It would be nice to hear some optimist science on that subject, of which there is some.

The trend, unfortunately for more than just us humans, is for more frequent/extreme conditions/events during (however long may be) the 'transitional phase', until Earth system(s) equilibrate into 'new normal' pattern(s) once current warming 'saturates' both source and sink processes/variables. However, Runaway Greenhouse possibility makes all fine-detail ditherings moot. Yes; Malthusian Trap always looms, as you know. Good luck to us all.

My post was basically a book report where one reports their conclusions and opinion. A critical analysis is verboten? Who am I to make a judgement about "good science". It is good science relative to some junk science. Of course this is an opinion. Is there something wrong with an opinion which does not undercut any substance of the article?

Name calling and accusation of lying.

A lot of you are really sick. Your emotional filters reveal loss of all common sense.

Real sick Os.

So sad. Anything I post from hereon will automatically be seen as bad through you jaundice eyes. Read Ayn Rand's Atlas Shrugged with special attention to the State Science Institute.

Got to hand it to to him, his outshining in the comedy class today, antigoracle, waterprophet sockpuppet's got a new sock, TURDgent clowning about on physorg posting his dumbest comments as ever LOL...

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